FAA Part 107 Drone Practice Test

Nimbus clouds are significant indicators of severe weather, particularly thunderstorms, making this choice correct. The presence of nimbus clouds, especially cumulonimbus, signifies a potential for heavy precipitation, lightning, and other violent weather phenomena associated with thunderstorms. This correlation is crucial for flight operations, as thunderstorms can create hazardous flying conditions due to turbulence, wind shear, and potential icing.

The other options do not accurately represent the characteristics of Nimbus clouds. For instance, nimbus clouds are not associated with clear weather, as they are typically thick and dark, indicating moisture in the atmosphere. While nimbus clouds can indicate turbulence, their primary association is with precipitation and storm conditions, which can lead to more severe turbulence linked directly to thunderstorms. Lastly, nimbus clouds are specifically defined by their ability to produce precipitation, so the idea that they contain no precipitation contradicts their fundamental nature.